This invention relates to novel benzylsulfonylureas. The compounds of this invention and their agriculturally suitable salts, are useful as agricultural chemicals, e.g., herbicides.
Netherlands Patent No. 121,788, published Sept. 15, 1966, discloses the preparation of compounds of the following Formula and their use as general or selective herbicides: ##STR1## wherein
R.sub.1 and R.sub.2 may independently be alkyl of 1-4 carbon atoms; and
R.sub.3 and R.sub.4 may independently be hydrogen, chlorine or alkyl of 1-4 carbon atoms.
U.S. Pat. No. 3,637,366 discloses compounds having the formula: ##STR2## wherein
R.sub.1 is hydrogen or lower saturated aliphatic acyl; and
R.sub.2 is hydrogen, 2-pyrimidinyl, pyridyl, amidino, acetyl or carbamoyl. The disclosed compounds are said to provide control of crabgrass, cress, endive, clover and Poa annua.
French Patent No. 1,468,747 discloses the following para-substituted phenylsulfonamides as being useful as antidiabetic agents: ##STR3## wherein
R=H, halogen, CF.sub.3 or alkyl.
Logemann et al., Chem. Ab., 53, 18052g (1959), disclose a number of sulfonamides, including uracil derivatives and those having the formula: ##STR4## wherein
R is butyl, phenyl or ##STR5##
R.sub.1 is hydrogen or methyl.
When tested for hypoglycemic effect in rats (oral doses of 25 mg/100 g), the compounds in which R is butyl and phenyl were most potent. The others were of low potency or inactive.
Wojciechowski, J. Acta. Polon. Pharm. 19, p. 121-5 (1962) [Chem. Ab., 59 1633 e] describes the synthesis of N-[(2,6-dimethoxypyrimidin-4-yl)aminocarbonyl]-4-methylbenzenesulfonamide: ##STR6## Based upon similarity to a known compound, the author speculated that the foregoing compound might have a hypoglycemic activity.
Substituted-pyrimidinyl sulfonylureas of the following formula, which are also para-substituted on the phenyl ring, are disclosed in Farmco Ed. Sco., 12, 586 (1957) [Chem. Ab., 53, 18052 g (1959)]: ##STR7## wherein
R=H or CH.sub.3.
U.S. Pat. No. 4,127,405 teaches compounds which are useful for controlling weeds in wheat having the formula: ##STR8## wherein
R.sub.1 is ##STR9##
R.sub.3 and R.sub.6 are independently hydrogen, fluorine, chlorine, bromine, iodine, alkyl of 1-4 carbon atoms, alkoxy of 1-4 carbon atoms, nitro, trifluoromethyl, cyano, CH.sub.3 S(O).sub.n -- or CH.sub.3 CH.sub.2 S(O).sub.n --;
R.sub.4 is hydrogen, fluorine, chlorine, bromine or methyl;
R.sub.5 is hydrogen, fluorine, chlorine, bromine, methyl or methoxy;
R.sub.7 is hydrogen, fluorine, chlorine, bromine, alkyl of 1-2 carbon atoms or alkoxy of 1-2 carbon atom;
R.sub.8 is hydrogen, methyl, chlorine or bromine;
R.sub.9 and R.sub.10 are independently hydrogen, methyl, chlorine or bromine;
W and Q are independently oxygen or sulfur;
n is 0, 1 or 2;
X is hydrogen, chlorine, bromine, methyl, ethyl, alkoxy of 1-3 carbon atoms, trifluoromethyl, CH.sub.3 S-- or CH.sub.3 OCH.sub.2 --; and
Y is methyl or methoxy; or their agriculturally suitable salts; provided that:
(a) when R.sub.5 is other than hydrogen, at least one of R.sub.3, R.sub.4, R.sub.6 and R.sub.7 is other than hydrogen and at least two of R.sub.3, R.sub.4, R.sub.6 and R.sub.7 must be hydrogen; PA1 (b) when R.sub.5 is hydrogen and all of R.sub.3, R.sub.4, R.sub.6 and R.sub.7 are other than hydrogen, then all of R.sub.3, R.sub.4, R.sub.6 and R.sub.7 must be either chlorine or methyl; and PA1 (c) when R.sub.3 and R.sub.7 are both hydrogen, at least one of R.sub.4, R.sub.5 or R.sub.6 must be hydrogen.
The presence of undesired vegetation causes substantial damage to useful crops, especially agricultural products that satisfy man's basic food and fiber needs, such as cotton, rice, corn, wheat, and the like. The current population explosion and concomitant world food and fiber shortage demand improvements in the efficiency of producing these crops. Preventing or minimizing loss of a portion of such valuable crops by killing, or inhibiting the growth of undesired vegetation is one way of improving this efficiency. A wide variety of materials useful for killing or inhibiting (controlling) the growth of undesired vegetation is available; such materials are commonly referred to as herbicides. The need still exists however, for more effective herbicides.